Corrected error code

[radarhere]

Extracting a change from the draft PR #6926

Pillow/src/_imagingft.c

Lines 168 to 170 in 599979c

	self->font_bytes = PyMem_Malloc(font_bytes_size);
	if (!self->font_bytes) {
	error = 65; // Out of Memory in Freetype.

On first glance, the PR simply stops this value from being hardcoded, by replacing it with FT_Err_Out_Of_Memory, as per https://freetype.org/freetype2/docs/reference/ft2-error_code_values.html.

However, 65 is actually not the out of memory error code. 65 is 0x41, and according to that FreeType doc, 0x40 is "out of memory", while 0x41 is "unlisted object". So this change is not just stylistic, but also corrects the error code.

[hugovk]

Good to merge, maybe add a Co-authored-by?

[radarhere]

Ok, I've updated the commit.